A03- Interactionist

• Evidence for the role of vulnerability and triggers

  Tienari et al investigated the combination of genetic vulnerability and parenting style. Children adopted from 19000 Finnish mothers with schiz. Adoptive parents assessed for child-rearing style and rates of schiz compared to control group of adoptees without any genetic risk.
• Tienari et al study findings

  Child-rearing style characterised by high levels of criticism and low levels of empathy implicated in development of schiz but only for those children with high genetic risk. Suggests genetic vulnerability and family related tress are important in development of schizophrenia.
• The orgininal diathesis-stress model is oversimple


  Multiple genes increase vulnerability to schiz, each having a small effect on its own, there is no single schizogene. Stress can also come in many forms including dysfunctional parenting. Thus, vulnerability and stress do not have on single gene.
• The orgininal diathesis-stress model is oversimple (Houston et al)


  Vulnerability can be the result of early trauma. Found chilhood sexual trauma emerged as a vulnerbaility factor whilst cannabis was a trigger.
• Support for effectiveness of combinations of treatments


  Turkington et al points out it is not possible to use combination of treatments without accepting an interactionist approach. Tarrier et al randomly allocated 315 people with schiz and CBT group, medicaiton and supportive counselling, control group.
• Support for effectiveness of combinations of treatments (Tarrier et al study findings)

  People in the two combination groups showed lower symptom levels rather than those in the control group but no difference in hospital re-admission rates. Shows interactionist approach is superior.
• We don't know exactly know how diathesis and stress work

  We do not fully understand the mechanisms by which the symptoms of schiz appear and how both vulnerability and stress produce them. It is clear however that either extreme biological and psychological positions should be abandoned.
• The treatment-causation fallacy

  Just because combinations of biological and psychological treatments are effective than either on their own does not necessarily mean the interactionist approach to schiz is correct. Perhaps the the underlying actual cause is not being dealt with.